Am I able to power this Xiao board directly via the 3.3V PIN?
I am stepping down 12V to whatever I like, and 3.3V could be ideal
What would happen if I connect up a USB while I’m doing this?
Hello! You would better not power this XIAO board directly via the 3.3V pin, but the VCC pin is allow 3.3V power in
best wish!
Cessarr
.
There is a schematic of the power supply section in post 2 of the link below. I think it will be helpful.
‘Charging characteristics of XIAO_nRF52840 and XIAO_ESP32C3 - #2 by msfujino’
The schematic indicates an LDO with ~200mV drop and a diode in front of that with ~325mV drop. A total of ~525mV drop. That means to me placing 3.3V on the 5V pin will get me ~2.8V. That seems problematic.
I must ask again, which pin is the VCC pin? 5V(VUSB?) or VBAT?
The linked schematic only mentions VCC_3V3
I have placed ~3.4V across the VUSB pin. Part does not appear to power up.
Please indicate which pin from Getting Started | Seeed Studio Wiki diagrams is the “VCC” pin